Applied Mechanics and Materials Vols. 713-715

Abstract: GPRS data transparent transmission modules are increasingly applied in different remote transmission occasions. With the development of remote monitoring system, there are some deficiencies need to be improved. This paper realizes a design of GPRS transparent transmission modules with multi-master communications function, the module integrates RS232 interface and supports UDP protocol. After experimental verification, the stability and practicability of the design is superior.

Abstract: The high-voltage SVC realizes the dynamic reactive power compensation through the real-time control over the breakover and cut-off of thyristor. Because the current passing through thyristor is large, the frequent break-make will lead to a lot of thermal loss, so it should be cooled in time. The self-cooled heat pipe cooling system is a traditional high-voltage SVC cooling system, which is expensive and heavy because it adopts relatively expensive copper product and aluminium product.This paper introduces a new heat pipe radiator. Compared to the traditional heat pipe radiators, it is light in weight, small in volume and low in cost. The performance test shows that the thermal resistance of the radiator is 0.064°C/W, that the main performance indexes are superior to those of the similar heat pipe radiators at home and abroad and that its self-cooling ability has achieved a high level. Therefore, it will greatly promote the promotion and application of this technology in China.

Abstract: With the serious problems caused by environment distruction, the large attention was taken to environmental protection. The coal pollution as one of the critical problems isurgently need to solve. Integrated Gasification Combined Cycle (IGCC), an advanced clean coal power generation system, is a main hotspot in energy and power field all over the world. This paper mainly focuses on the technology, development trend and the problems of IGCC in Tianjin. The success of IGCC greatly enhances the international influence of our country in dealing with the global climate change,which also makes great significance in the development and storage of China's coal-fired power generation.

Abstract: Slagging is a very complicated physical and chemical process which refers to several scientific cores such as combustion, multiphase flow, heat and mass transfer etc. This paper is to build a mathematical modeling of fuzzy comprehensive judgment and to predicate the distribution of slagging on the heated surface by utilizing the theory of fuzzy mathematics. Then a prediction is made in the boiler of Tuoketuo power plant from Datang Corporation with this method, the results are better consistent with the actual conditions.

Abstract: As distribute power generation and micro-grid technology develops, more and more researchers attach importance to the problems of power quality in micro-grid, especially the problem of harmonic. This paper describes the impact and harm harmonic has on the power quality of the power grid. It introduces a revised method of managing micro-grid harmonics which uses an active power filter (APF), and the control method of APF is different from the traditional one. It also establishes the simulation model of micro-grid, analyze the simulation results and experiment in actual micro-grid to verify the effectiveness of the proposed method.

Abstract: Photovoltaic (PV) power generation is one of important direction of future energy development by most countries. The research on power flow calculation of power system with grid-connected photovoltaic generation based on Matpower is given in this paper. Firstly, a stochastic model of PV system is presented in the paper. Then, Matpower is used in the simulation of power flow for IEEE 57 node system. Simulation results of with PV generation and without PV generation in IEEE 57 node system are presented. Comparison between the results shows that adding PV generation in power system will have great influence on power flow of power system.

Abstract: In the process of China's ultra high-voltage (UHV) construction, Henan UHV power grid is the important part. Summer great load mode of Henan power gird is chosen as the typical method. In the background of completing Nanyang UHV extension project, based on single pole running and double pole running of Hami-Zhengzhou UHVDC project respectively, it is simulated and analyzed. The results indicate that power grid cannot maintain stability when single pole block fault or double pole block fault occurs. Through theoretical analysis and simulation, under UHV AC running certain limit, HVDC latching grid is stable. Under UHV DC running certain limit, HVDC latching grid is stable. Based on continuous simulation, this paper obtained the coordinated operation of area UHV AC and DC.

Abstract: A new type powertrain system architecture for city electric bus was introduced, which combines the function of Extended-Range Electric Vehicle (E-REV) and Plug-in Hybrid Electric Vehicle (P-HEV). Five driving modes were designed and its dynamics were analyzed. Numerical method on dynamics was proposed. The dynamic performance parameter of five drive modes were calculated and analyzed. The results indicate that the dynamic performance reaches the limit value at full drive mode and meet the requirement of city bus.

Abstract: Currently, most of the boilers in power plant are designed by the heat balance based on first law of thermodynamics only, and it analyses the condition of using energy from the perspective of quantity of energy. However, The real energy utilization should be justified not only from the quantity but also from the quality, because the quality of energy based on second law of thermodynamics can reflect the irreversibility in processes and components. In order to revealing the real energy losses, we must establish exergy analysis model of 130t/h Biomass-Fired Boiler. This article calculates the exergy losses of all kinds of boiler surface and the overall exergy efficiency of boiler, together with exergy distribution characters analysis result of 130t/h Biomass-Fired Boiler. The results obtained open out the greatest exergy loss and the place to generate these losses of boiler, and provide scientific gist for improving utilization of boiler energy.

Abstract: According to data about GIS breakdown maintenance in Maintenance Branch of State Grid Chongqing Electric Power Company during recent years, GIS accident of Chongqing Electric Power Company that happens every year is internal fault of local air chambers (such as breaker, PT and bus) in most cases. Once accident happens, a high requirement will be proposed for water prevention and damp prevention at the site during either on-site inspection for the accident cause or replacement for the damaged equipment. In order to effectively cover the first hole of the opened GIS air chamber and make the operation environment meet rain-proof and damp-proof requirements during internal examination for GIS air chamber, a design scheme of mobile GIS maintenance room is proposed in this paper. SF₆ detection equipment as well as temperature and humidity examination equipment is installed in the maintenance room, so as to measure multiple parameters and to guarantee light transmission, ventilation and fire resistance. It is convenient for installation and disassembly, and the space can be adjusted. It is suitable for GIS equipment maintenance at the voltage class of 220kV.